Abstract:

Thin-film photovoltaics are of great interest due to decreased manufacturing costs, improved environmental sustainability and the potential for flexible, semi-transparent, and light-weight modules. The scientific literature contains a plethora of work incorporating wavelength scale nanostructures within thin-film solar cells to increase power conversion efficiency by trapping light inside solar cell absorbing layers. One category of nanostructures, namely plasmonic nanoparticles, theoretically show great promise for their light-trapping abilities but experimental success has been limited. In this work, solar cells were designed and fabricated to incorporate multiple light-trapping mechanisms, including optical cavity resonances, waveguide mode excitation, and plasmonic effects. Due to our novel design considerations, we demonstrate a 33% increase in Jsc originating from plasmon-based enhancement mechanisms. The experimental results are complemented and confirmed by well-matching simulations which are used to further investigate the light-trapping mechanisms. The concepts demonstrated in this work can be directly translated to next-generation transition metal dichalcogenide photovoltaic devices.